During the last decades, electronic devices and components have been significantly reduced in size. This has a direct impact on the dimensions of internal components and metallization of such devices. Solder paste is widely used for point contacts between the different components or layers inside electronic devices. These paste are composed of metallic powders and of fluxes, to ensure proper melting and adhesion to other components. The metallic components in the soldering paste is generally in the form of a “low melting point alloy” or “low melting point metal” and the size distribution of such metallic powder depends on size of the point contact. Smaller electronic devices and components requiring smaller contacts, hence a growing demand is seen for solder paste with metallic powders having smaller size distribution. It is not uncommon to have required or requested particle size distribution mostly under 20 and even under 10 microns.
There are multiple other applications for fine metallic powders, such as metal injection forming, thermal spraying, thermal spray welding, 3D printing and many more.
Conventional techniques (atomization, centrifugal disintegration, water atomization . . . ) can produce fine powders, but the particle size standard deviation and the spherical shape of the particles are difficult to achieve from low melting point alloys. This often leads to a low recovery of the produced powder in a defined size fraction from these technologies.